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January 1995

Biology 30

Grade 12 Diploma Examination

^Iberia

EDUCATION

Copyright 1995, the Crown in Right of Alberta, as represented by the Minister of Education, Alberta
Education, Student Evaluation Branch, 11160 Jasper Avenue, Edmonton, Alberta, T5K 0L2. All rights
reserved. Additional copies may be purchased from the Learning Resources Distributing Centre.

Special permission is granted to Alberta educators only to reproduce, for educational purposes and on a
non-profit basis, parts of this examination that do not contain excerpted material only after the
administration of this examination.

Excerpted material in this examination shall not be reproduced without the written permission of the
original publisher (see credits page, where applicable).

UNIVERSITY LIBRARY
UNIVERSITY OF ALBERTA

January 1995

Biology 30

Grade 12 Diploma Examination

Description

Time: 2.5 h. You may take an
additional 0.5 h to complete the
examination.

Total possible marks: 80

This is a closed-book examination
consisting of

• 48 multiple-choice and 8 numerical -
response questions each with a value
of one mark

• 2 written-response questions, each
worth 12 marks

This examination contains sets
of related questions.

A set of questions may contain
multiple-choice and/or numerical -
response and/or written-response
questions.

When required, a grey bar will be
used to indicate the end of a set.

Tear-out data pages are included at the
back of this booklet.

The perforated pages at the back of this
booklet may be torn out and used for
your rough work. No marks will be
given for work done on the tear-out
pages.

Instructions

• Fill in the information required on the
answer sheet and the examination
booklet as directed by the presiding
examiner.

• You are expected to provide your own
scientific calculator.

• Use only an HB pencil for the
machine-scored answer sheet.

• If you wish to change an answer, erase
all traces of your first answer.

• Consider all numbers used in the
examination to be the result of a
measurement or observation.

• Do not fold the answer sheet.

• The presiding examiner will collect
your answer sheet and examination
booklet and send them to Alberta
Education.

• Read each question carefully.

• Now turn this page and read the
detailed instructions for answering
machine-scored and written-response
questions.

Multiple Choice

• Decide which of the choices best
completes the statement or answers
the question.

• Locate that question number on the
separate answer sheet provided and
fill in the circle that corresponds to
your choice.

Example

This examination is for the
subject of

A. biology

B. physics

C. chemistry

D. science

Answer Sheet

• (D © ®

Numerical Response

• Record your answer on the answer
sheet provided by writing it in the
boxes and then filling in the
corresponding circles.

• If an answer is a value between 0 and 1
(e.g., 0.25), then be sure to record the 0
before the decimal place.

• Enter the first digit of your answer
in the left-hand box and leave any
unused boxes blank.

Examples

Calculation Question and Solution

The average of the values 21.0, 25.5, and
24.5 is .

(Record your answer to three significant
digits in the numerical-response section of
the answer sheet.)

Average = (21 .0 + 25.5 + 24.5)/3
= 23.666

= 23.7 (rounded to three digits)

Record 23.7 on the
answer sheet

•

Written Response

Correct-order Question and Solution

When the following subjects are arranged in

alphabetical order, the order is .

(Record your four-digit answer on the numerical-
response section of the answer sheet.)

1 physics

2 chemistry

3 biology

4 science

Answer 3214

• Write your answers in the examination
booklet as neatly as possible.

• For full marks, your answers must be
well organized and address all the main
points of the question.

• Relevant scientific, technological, and/or
societal concepts and examples must be
identified and explicit.

Record 3214 on the
answer sheet

•

• Descriptions and/or explanations of
concepts must be correct and reflect
pertinent ideas, calculations, and
formulas.

• Your answers should be presented in a
well-organized manner using complete
sentences, correct units, and significant
digits where appropriate.

Selection Question and Solution

The birds in the following list are numbered

(Record your answer in ascending numerical order
in the numerical-response section of the answer
sheet.)

1 dog

2 sparrow

3 cat

4 robin

5 chicken

Answer 245

Record 245 on the
answer sheet

•

ill

Do not turn the page to start the
examination until told to do so by the
presiding examiner.

Digitized by the Internet Archive
in 2016

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Scientists study disorders of the nervous and endocrine system to find treatments for
the disorders and to extend their knowledge of these systems.

Use the following information to answer the next two questions .

Alzheimer’s disease is a degenerative, incurable, and often fatal brain disorder. It is
characterized by progressive memory loss and the inability to think, speak, or perform basic
tasks.

Autopsy studies of the brain tissue of Alzheimer’s patients usually show abnormalities such as:

• tangled and twisted protein filaments within neuron cell bodies

• clusters of degenerated axon terminals

• death of certain neurons that are responsible for the production of a common
neurotransmitter

• growth within neurons of patches composed of a protein called beta-amyloid

1. Within a neuron, the production of beta-amyloid patches is primarily controlled by
substances in the

A. myelin sheath

B. cell body

C. dendrite

D. axon

2. Which secretion is most likely lacking in the brain of an Alzheimer’s patient?

A. ATP

B. Acetylcholine

C. Transfer RNA

D. Cholinesterase

Use the following information to answer the next two questions.

Huntington Disease

Many genetic disorders in humans result in some behavioural abnormality. One example is
Huntington disease (HD), which is controlled by the presence of a dominant gene. This disease
affects all parts of the nervous system, including the brain. Symptoms of HD usually appear
after age 40 and include a gradual loss of motor function and coordination. Degeneration of the
nervous system is progressive and produces personality changes. Affected individuals become
unable to care for themselves. These symptoms indicate that the disease affects some parts of
the brain more than others.

3. Which row identifies the degree to which certain parts of the brain are most likely
affected by HD?

Row

Relative Effect of HD on Parts of the Brain

Cerebrum

Cerebellum

Pituitary

Hypothalamus

slight

significant

slight

significant

slight

significant

slight

significant

slight

Use this additional information to answer the next question.

A person with HD has elevated levels of quinolinic acid. Quinolinic acid is an amino acid that
excites neurons but also acts as a neurotoxin (poison). It is produced when tryptophan is
metabolized by the body.

4. This additional information supports the hypothesis that the gene that causes HD is

A. a structural gene that contains information used to produce an enzyme that
metabolizes tryptophan

B. a mutant gene that promotes the action of enzymes that metabolize
quinolinic acid

C. a regulatory gene that produces an enzyme that metabolizes quinolinic acid

D. an oncogene that activates enzymes that metabolize tryptophan

Use the following list to answer the next question.

Some Events that Occur in the Nervous System

1 A motor neuron stimulates the effector.

2 Nerve tracts in the medulla oblongata are activated.

3 The brain interprets the sensation of pain.

4 A sensory neuron is depolarized.

5 A receptor is stimulated.

6 The motor cortex initiates movement.

7 An impulse is initiated in an intemeuron.

Numerical Response

ill When a person’s hand touches a very hot object, a reflex arc is activated, which
causes the person to quickly withdraw the hand. Provide the correct sequence of
events that occurs in this reflex arc by selecting four events from the list and
arranging them in the proper order.

Answer:

First event Second event Third event Fourth event

(Record your four-digit answer in the numerical-response section of the answer sheet.)

5. Many blind people have damaged
sensory receptors in the eyes but
undamaged optic nerves. To assist
these people, an artificial eye would
have to replace the function of which
structure shown in the diagram at
the right?

A. 1

B. 2

C. 3

D. 4

6. An optometrist who wants to dilate the pupil to study the interior of the eye would
likely administer a drug to stimulate the

A. central nervous system

B . somatic nervous system

C. sympathetic nervous system

D. parasympathetic nervous system

Use the following information to answer the next two questions.

Damage to hair cells in the inner ear was thought to permanently impair the sense of balance.
Recent research indicates that humans and guinea pigs have the ability to form new hair cells in
the utricle. In experiments, these hair cells were chemically destroyed. After some time, new
hair cells formed. These new cells eventually connected with neurons. Researchers have yet to
discover the internal body stimuli that trigger the formation of the new cells.

7. In the experiments, newly formed hair cells connected with neurons. What type of
neurons would these be?

A. Motor neurons

B . Sensory neurons

C. Somatic neurons

D. Association neurons

8. In order to develop a procedure that would restore hearing in individuals with
hearing loss caused by damage to hair cells, similar research must be done on the
hair cells found in the

A. saccule

B . cochlea

C. auditory canal

D. semicircular canals

9. Both giantism and dwarfism are disorders caused by a malfunction of
which gland or glands?

Gonads

Thyroid

Pituitary

Adrenals

Use the following information to answer the next question.

Possible Symptoms of Diabetes Mellitus

Increased insulin production

Decreased insulin production

Increased blood glucose level

Decreased blood glucose level

Increased cellular absorption of glucose

Decreased cellular absorption of glucose

Increased urine production

Decreased urine production

Numerical Response

|3 Pat, a 14 year-old student, has diabetes mellitus. Which four of these symptoms
would Pat likely show, if untreated?

Answer:

(Record your four-digit answer in ascending numerical order in the numerical-response section of
the answer sheet.)

10. Which hormone acts antagonistically (oppositely) to insulin?

A. Somatotropin

B . Epinephrine

C. Thyroxine

D. Glucagon

Use the following information to answer the next three questions.

Amino Acid Sequence in Insulin

Dr. Frederick Sanger and his colleagues in England worked out the exact sequence of 5 1 amino
acids in the insulin molecule. One part of that sequence of amino acids is:

— alanine — lysine — proline — threonine —

11. Which sequence of nitrogen bases in DNA encodes information to make this part of
the insulin molecule?

A. — CG A — TTT — GGT — TGA —

B. — CGT — AAA — GGT — ACT —

C. — GCU — AAA — CCA — ACU

I). — GCG — AAG — CCA — ACG —

12. Which change in the structure of mRNA would not cause the amino acid threonine
to be replaced with another amino acid?

A. ACG -> UCG

B. ACA -> AUC

C. ACC -> UGG

D. ACU -> ACC

13. Although all normal human insulin molecules contain a specific sequence of amino
acids, the nucleotide sequence in the insulin gene may vary slightly from person to
person. This variation can occur because

A. the type of amino acids in insulin does not affect its function

B. a specific amino acid can be represented by more than one codon

C. the sequence of amino acids in insulin does not affect its function

D . a specific codon can be represented by more than one polypeptide

Use the following information to answer the next question.

Scientists from the All India Institute of Medical Sciences in New Delhi recently
conducted research on the reproductive endocrine functions of men with
hypothyroidism. Their objective was to study the relationship between thyroid
hormones (triiodothyronine and thyroxine)* and hormones related to reproduction.
Eight men with symptoms of hypothyroidism were chosen for the study. Blood
samples from these men were analyzed before treatment for hypothyroidism began.
Some of the data are presented in table 1 .

Table 1:

Data Obtained from Eight Patients with Hypothyroidism and
Normal Ranges of Some Hormone Concentrations in Blood

Patient

Age

(years)

TSH

(units)

Triiodothyronine

(units)

Thyroxine

(units)

>100

36.0

2.2

>100

32.0

0.0

>100

26.0

1.0

>100

28.0

0.5

>100

40.0

0.5

>100

50.0

3.0

>100

46.0

2.0

>100

0.7

Normal

range

—

0-8

80-160

5-11

* Two thyroid hormones with similar functions

Written Response - 12 marks

1 1, | a. Based on the data in table 1, define hypothyroidism in terms of the
function of the thyroid gland.

b. Explain why TSH concentrations in the eight patients differed from the
normal range?

Continued

For

Department
Use Only

(1 mark)

For

Department
Use Only

(1 mark)

c. Describe one possible treatment for hypothyroidism suggested by the
data in table 1.

(3 marks)

d. Identify three symptoms of hypothyroidism, other than hormone

concentrations in the blood or effects on reproduction, likely shown by
the patients.

Before treatment for hypothyroidism began, blood samples from the eight patients
were tested for the presence of some hormones related to reproduction. Similar
tests were performed after treatment for hypothyroidism was complete. A control
group was tested in a similar manner. The average blood concentrations of these
hormones related to reproduction are shown in table 2.

Table 2: Average Blood Concentrations of Some Hormones Related to

Reproduction in Eight Patients Before and After Treatment for
Hypothyroidism and in a Control Group

Group

Hormone Concentration
(units/L of blood)

FSH

Testosterone

Patients before treatment

19.0

6.0

5.5

Patients after treatment

7.0

3.0

13.0

Control

6.0

3.5

23.5

Continued

e. Draw a bar graph to illustrate the data in table 2.

f. Why would a man with hypothyroidism produce fewer sperm than a
man with a normally functioning thyroid?

For

Department
Use Only

(3 marks)

(1 mark)

g. Explain the differences in the production of FSH and testosterone by
the group of eight patients before treatment and by the control group.

(2 marks)

Reproductive processes may be affected by disease, the environment, or the use of
technology.

14. The sample of tissue used to make this cross section would be obtained from the

A. testis

B. epididymis

C. vas deferens and urethra

D. seminal vesicle and prostate

15. The cell that contains a single X or Y chromosome is labelled

A. 1

B. 2

C. 3

D. 4

Use the following information to answer the next three questions.

A. fertilization of eggs

B . development of follicles

C. movement of sperm into the uterus

D. secretion of estrogen and progesterone

17. Gonorrhea, a sexually transmitted disease, may cause an infection in the structure
labelled 4. This condition could result in sterility because

A. ovulation would be disrupted

B . menstruation would not occur

C. implantation would be prevented

D. fertilization would not be possible

18. Which structure produces a hormone that prevents uterine contraction during the
first weeks of pregnancy?

A. 2

B. 3

C. 4

D. 5

Use the following information to answer the next question.

A Reproductive Technology

Reproductive technology may be used when people have difficulty conceiving children.

In vitro fertilization (IVF) is a procedure in which eggs are removed from a woman’s ovary and
placed in a culture dish containing sperm from a male donor. After fertilization occurs, an
embryo is inserted into the uterus through the vagina.

19. The female menstrual cycle has several phases. Implantation of the fertilized egg
in the IVF procedure would have the greatest chance of success if it were done
during the

A. corpus luteal phase when progesterone levels are high

B. corpus luteal phase when FSH levels are high

C. follicular phase when estrogen levels are high

D. follicular phase when LH levels are high

20. Researchers have discovered that exposure to an electric field causes the caps
(acrosomes) of sperm to burst before contact with ova. How might exposure of
sperm to an electric field affect the success rate of in vitro fertilization?

A. The success rate would improve because sperm would be more motile.

B . The success rate would decline because the nuclei of sperm would be altered.

C. The success rate would decline because sperm would not be able to
penetrate ova.

D. The success rate would improve because more nutrients would be available to
ensure survival of sperm.

21. In humans, a sperm and an egg are similar in that both

A. require normal body temperature for maturation and development

B. contribute equally to the cytoplasm of the zygote

C. are inactivated by a solution with a pH of 7 to 9

D. contain the same number of chromosomes

22. Which statement about the events that occur during childbirth is correct?

A. An increase in prolactin causes relaxation of pelvic ligaments.

B. An increase in oxytocin causes contraction of uterine muscles.

C. A decrease in estrogen causes contraction of abdominal muscles.

D. A decrease in progesterone causes relaxation of placental membranes.

Use the following information to answer the next three questions.

Fetal Alcohol Syndrome

Fetal Alcohol Syndrome (FAS) is a condition that develops in a fetus as a result of the
ingestion of alcohol (ethanol) by a pregnant woman. The effects on the fetus include mental
retardation, slow growth, and the development of a small head, narrow eye slits, and a
defective heart. These changes are not reversible. Pregnant women who consume 25 mL of
pure alcohol daily (equivalent to two or three bottles of beer) have a 2% chance of giving birth
to a child with FAS.

Most doctors urge pregnant patients to avoid the use of drugs of all kinds. The use of drugs
such as alcohol, heroin, cocaine, and morphine may cause a child to be bom addicted.

23. Some women who consume 25 mL of absolute alcohol daily may have a

significantly higher than 2% risk of having a child with FAS. The additional factor
that likely contributes most to this increased risk is a woman’s

A. body mass

B . emotional state

C. exercise routine

D. choice of brand of alcoholic beverage

24. An infant can be bom with a dmg addiction because

A. a child can acquire all of its mother’s habits

B . a child can inherit some of its mother’ s addictions

C. placental membranes promote the mixing of maternal blood with fetal blood

D. placental membranes are permeable to substances other than nutrients and wastes

Continued

Use this additional information to answer the next question.

Alcohol is normally metabolized as follows:

Alcohol

Alcohol ;
dehydrogenase

Acetaldehyde

Aldehyde

dehydrogenase

Acetic acid

Acetaldehyde is a product of alcohol metabolism that contributes to fetal damage. Acetic acid
may be used for energy production or fat synthesis.

25. Which row indicates the rate of action of two enzymes in a pregnant woman’s body
that would put a fetus at the greatest risk of developing FAS?

Row

Relative Rate of Action of Enzymes in a Pregnant Woman’s Body

Alcohol dehydrogenase

Aldehyde dehydrogenase

fast

slow

fast

slow

Data collected by scientists reveal interactions among organisms and populations.

Use the following graph to answer the next two questions.

Population of Mice in a Farmer’s Field (1979-1992)
I II III

26. On the graph, sections I, II, and III respectively show the

A. stationary phase, growth phase, and lag phase of a closed population

B . lag phase, growth phase, and stationary phase of a closed population

C. stationary phase, growth phase, and lag phase of an open population

D. lag phase, growth phase, and stationary phase of an open population

27. The trend shown in section II of the graph might have continued for an extra year if

A. predators had been allowed to roam freely

B. irrigation had increased the growth of vegetation

C. more consumers had been added to the environment of the mice

D. traps had been set to prevent emigration and immigration of mice

Use the following information to answer the next three questions.

Historical plant populations can be
examined by removing core samples of
earth and microscopically examining
them for the types of pollen present.
The graph shows an analysis of pollen
collected at various depths from a
grassland site in southern Alberta. The
samples were obtained by drilling into
the earth and then removing the entire
core sample intact. The total depth
sampled has accumulated since the end
of the last glacial period, approximately
13 000 years ago. Each 0.3 m of depth
represents about 1 000 years.

Grasses

Spruce

Fir

Pine

Mixed deciduous

Pollen Core Samples Taken from a
Grassland Area in Southern Alberta

Percent of sample

28. The change in the vegetation over the last 13 000 years is called

A. succession

B. colonization

C. serai staging

D. a climax community

Continued

29. Select the row that correctly identifies the sequence of communities this site has
supported from 13 000 years ago up to and including the present.

Row

Sequence of Communities

Grass-deciduous — > pine-spruce — > pine — > fir-spruce

Fir-spruce — > pine-deciduous — > pine — » grass-deciduous

Pine-grass — » pine-fir— > pine- spruce —> spruce-deciduous

Grass-deciduous — » pine — » fir-spruce — > spruce-pine

30. According to the data, in what way and when did the climate dramatically change in
southern Alberta?

A. The climate became warm and dry 12 000 to 13 000 years ago.

B. The climate became cool and moist 7 000 to 8 000 years ago.

C. The climate became cool and moist 3 000 to 4 000 years ago.

D. The climate became warm and dry 1 000 to 2 000 years ago.

Use the following information to answer the next two questions.

In the Antarctic, James McClintock
noticed that small amphipods
(crustaceans) captured small free-
floating snails. The snails were
bright orange in colour and half the
size of the amphipods. An
amphipod held a snail on its back
with 4 of its 14 legs. The snails
were released unharmed when it got
dark.

In a laboratory, McClintock
separated populations of snails from
populations of amphipods and
placed some small fish with each
group. The fish ate the amphipods
but ate only a few of the snails and
immediately spit them out.

When amphipods with snails on
their backs were placed in the tank
that originally contained snails, the
fish did not eat the amphipods and
actually avoided them. McClintock
ground up some snails and formed
them into pellets to feed the fish.
When these pellets were fed to the
fish, they immediately spit them out.

An Amphipod with a
“Piggy-Backing” Snail

Amphipod

31. The term that best describes the relationship between the amphipod and the snail is

A. commensalism

B. mutualism

C. parasitism

D. predation

32. Why did the fish not eat the amphipods with snails on their backs?

A. The snails provided camouflage for the amphipods.

B. The fish learned to avoid the amphipods because the amphipods mimicked
the snails.

C. The foul taste of the snails was absorbed by the amphipods and the fish
learned to avoid them.

D. The fish avoided eating amphipods carrying snails because they recognized
the warning coloration.

Use the following information to answer the next four questions.

A Zebra Mussel Takeover

The European zebra mussel, a small bivalve mollusk, was first discovered in North America in
1988. It was found in Lake St. Clair, which connects Lake Huron to Lake Erie. By 1991, the
mussel had spread to all the Great Lakes as well as the Illinois River. Scientists think the
mussels were carried into the Great Lakes in the ballast water of freighters. During the
summer of 1993, the Mississippi River flooded its banks and picked up zebra mussels from
the Illinois River. The flood waters carried the mussels into creeks, lakes, and ponds along its
southerly route.

Zebra mussels spawn up to five times a year and release about a million eggs per spawning.
The larvae travel in water for five to 30 days before they settle onto something stationary. The
mussels secrete strong threads that tether them to submerged rocks, docks, hulls of boats, and
sewage and water treatment intake-pipes. As many as 94 000 zebra mussels can occupy a
surface area of 1 m2.

Zebra mussels feed by drawing water over their gills with siphons. They compete with native
mussels and fish for suspended food such as algae. Natural predators, such as ducks and
crayfish, have not been able to keep them under control. The use of chemical pesticides, such
as chlorine, is costly and can lead to the formation of cancer-causing agents in water systems.

33. The abiotic factor that caused the zebra mussel to spread from the Great Lakes

south into the United States rather than north into Canada was the difference in the

A. diversity of predators in Canada and the United States

B. food supply in the waterways of the United States and Canada

C. level of industrial development of the United States and Canada

D. natural water drainage patterns of Canada and of the United States

Continued

34. The spread of the European zebra mussel in North America from 1988 through
1993 is an example of a species with populations that are distributed

A. in clumps and K-selected

B. randomly and K-selected

C. in clumps and r-selected

D. randomly and r-selected

Numerical Response

Q Suppose that a population of 3 500 mussels occupied a rectangular territory 2.00 m
by 2.00 m. Calculate the average density of this mussel population.

Answer: /m2

(Record your answer to three significant digits in the numerical-response section of the
answer sheet.)

Numerical Response

gH Given that one mussel releases one million eggs per spawning and assuming that

the survival rate is 0.020%, calculate the maximum number of surviving individuals
produced in two generations originating with one mussel. Express your answer in
scientific notation in the form w x 10^ mussels. What is the value of w when the
answer is expressed in scientific notation?

Answer:

(Record your answer to two significant digits in the numerical-response section of the answer sheet.)

An understanding of the principles of cell division and genetics is required to make
appropriate choices about the use of biotechnology.

Use the following information to answer the next two questions.

Life Cycle of Sea Lettuce (Green Alga)

35. Which conclusion about the life cycle of sea lettuce is supported by the diagram?

A. The spore is diploid.

B . The zygote is haploid.

C. The sporophyte is diploid.

D. The gametophyte is diploid.

36. Assuming that the diploid chromosome number for this species is 12, what is the
chromosome number at stages labelled W, X, and Y respectively?

A. 6, 6, and 12

B. 6, 12, and 12

C. 6, 12, and 24

D. 12, 12, and 24

37. Compared to asexual reproduction, one advantage of sexual reproduction is the

A. development of haploid individuals

B . development of genetically identical individuals

C. increased production of offspring in one life cycle

D. increased chance of producing offspring adaptable to environmental change

Use the following information to answer the next question.

Events That Occur During DNA Replication
(Arranged in Random Order)

1 Hydrogen bonds form between nucleotide bases.

2 An enzyme acts like a pair of scissors to break the weak hydrogen bonds between the
nitrogen bases.

3 At the replication fork, the DNA template strands determine the sequence of the
nucleotides that are being replaced.

4 A purine or pyrimidine is inserted on a matching nucleotide of the polynucleotide strand.

5 Nitrogen bases of the polynucleotide strand separate.

38. The correct sequence of events that occurs during DNA replication is

A. 2, 3, 5, 1, and 4

B. 2, 5, 3, 4, and 1

C. 3, 2, 5, 4, and 1

D. 3, 5, 2, 1, and 4

Use the following diagram to answer the next two questions.

39. What is a likely cause of the abnormality shown in this karyotype?

A. Crossing over of autosomes

B. Nondisjunction of autosomes

C. Crossing over of sex chromosomes

D. Nondisjunction of sex chromosomes

40. Which technology would be best suited to identify a fetus with this disorder?

A. Ultrasound

B. X-ray imaging

C. Amniocentesis

D. DNA fingerprinting

Use the following information to answer the next question.

Some Characteristics of Cell Division

1 DNA is replicated just before cell division begins.

2 Duplicated chromosomes pair with their homologues.

3 Diploid cells are ultimately produced.

41. Which row correctly identifies the type of cell division described by each
numbered statement?

Row

Statement 1

Statement 2

Statement 3

both mitosis and
meiosis

meiosis only

mitosis only

both mitosis and
meiosis

mitosis only

meiosis only

both mitosis and
meiosis

mitosis only

both mitosis and
meiosis

meiosis only

Use the following information to answer the next two questions.

In shorthorn cattle, coat colour may be red, white, or roan. Crosses between a red bull and a
white cow produce only roan offspring.

42. The alleles for coat colour in shorthorn cattle demonstrate

A. sex-linkage

B . crossing over

C. codominance

D. nondisjunction

El If a roan shorthorn is crossed with a white-coated shorthorn, what is the
probability that the offspring will be a roan shorthorn?

Answer:

(Record a value from 0 to 1 rounded to two significant digits in the numerical-response section of the
answer sheet.)

Use the following information to answer the next three questions.

In guinea pigs, black coat (B) is dominant over white coat (b), and straight hair (S) is dominant
over curly hair (s). Each pair of alleles assorts independently.

Two guinea pigs mated. The types of gametes produced by the parents are shown in the
Punnett square. Possible genotypes of offspring resulting from the mating are indicated in the
centre of the Punnett square as genotype 1 to genotype 8.

genotype 1

genotype 2

genotype 3

genotype 4

genotype 5

genotype 6

genotype 7

genotype 8

43. Which row correctly identifies the phenotypes of both parents?

Row

black-straight

black-curly

black-straight

black-curly

white-straight

white-curly

black-straight

44. The Punnett square indicates that the parent guinea pigs

A. produced eight offspring, all with different genotypes

B. produced eight offspring, half of which have at least one of the dominant traits

C. are likely to produce a higher proportion of offspring with black coats than
offspring with curly hair

D. are likely to produce a higher proportion of offspring with white coats than
offspring with straight hair

Numerical Response

ES Choose the correct genotype number for each description of guinea pig offspring.

Genotype number:

Description of offspring: Homozygous Have the same White coat colour

recessive for genotype as and heterozygous

both traits genotype 3 for hair type

(Record your three-digit answer in the numerical-response section of the answer sheet.)

45. A new insecticide functions as a mutagen. It seems to have little effect when

applied to an adult insect population. However, the insect’s offspring have a variety
of lethal defects. This new insecticide likely affects the process of

A. mitosis in gonads

B. meiosis in gonads

C. mitosis in somatic cells

D. meiosis in somatic cells

Use the following information to answer the next three questions.

Phenylketonuria

Phenylketonuria (PKU) is a genetic disorder, the symptoms of which result from the inability of
a person to produce the enzyme necessary to metabolize the amino acid phenylalanine.
Production of the normal enzyme is controlled by a dominant allele. Without this enzyme,
phenylalanine accumulates in a person’s body and causes mental retardation by inhibiting the
normal development of the nervous system.

The symptoms of PKU are not usually evident immediately at birth, but develop rapidly after
birth if an affected child is not put on a special diet. After ten years of age, the nervous system
is fully developed and the child’s diet need no longer be strictly controlled.

46. The initial cause of PKU in an affected child likely results from the presence
of abnormal

A. ribosomal RNA

B. messenger RNA

C. DNA in cell nuclei

D. DNA in cell mitochondria

Continued

Use this additional information to answer the next two questions.

47. Which is a valid conclusion about the genotypes for the alleles for PKU of

individuals II, 2 and II, 3?

A. They are both heterozygous because their sister has PKU.

B. They are both homozygous-dominant because their parents have
normal phenotypes.

C. Without further evidence, it cannot be determined if both are
homozygous-dominant or heterozygous.

D. Without further evidence, it cannot be determined if both are
homozygous-recessive or heterozygous.

Numerical Response

ftfl If the individuals in this pedigree represented a distinct population, how many of
the 21 people could be expected to be heterozygous for PKU?

Answer: people

(Record your answer in the numerical-response section of the answer sheet.)

Use the following information to answer the next two questions.

Hemophilia is a disorder characterized by abnormal blood clotting. This disorder is an
X-linked recessive trait.

48. A man who does not have hemophilia, but whose father did, is married to a woman
who has no history of hemophilia in her family. Would genetic screening be
necessary if this woman gets pregnant?

A. No, because there is little probability that the disorder would occur regardless
of the sex of the offspring.

B. Yes, because the man’s father had hemophilia and it may skip a generation.

C. No, because there is only a 25% chance that a male child would get the
disorder.

D. Yes, because there is a high probability of mutation for X-linked genes.

Numerical Response

KJ A normal woman whose father had hemophilia is married to a man who has
hemophilia. If they have a child, what is the probability that the child would
have hemophilia?

Answer:

(Record a value from 0 to 1 rounded to two significant digits in the numerical-response section of the
answer sheet.)

Use the following information to answer the next question.

In the 19th century, individuals who were not among the “normal” population were often thought
to be failures or defectives. Early in the 20th century, the interaction of genetics, law, and society
resulted in policies of enforced sterilization, restrictive immigration, and institutionalization of
those thought to be genetic defectives. As this century closes, society will have difficult choices to
make about the legality, morality, and economics of applying genetic knowledge and technology.
The difficulty of this situation is summarized in the words of a famous geneticist, Theodosius
Dobzhansky (b.1900 - d.1975):

“If we enable the weak and the deformed to live and produce more of their kind, we face the
prospect of a genetic twilight (decline). But if we let them die or suffer when we can help
them, we face the certainty of a moral twilight.”

Written Response - 12 marks

1 2. | Consider the following proposal:

People with genetic abnormalities should not be discouraged from having families.
Doctors should attempt to treat every genetically related health problem and to keep
people alive at all cost.

If this proposal were initiated, there would be many effects on our society. Describe
three ethical medical technologies that would reduce the financial costs created by
initiating this proposal. Evaluate the proposal from both a genetic and a moral point
of view.

Your response should include the following information:

• A description of three medical technologies that are ethical and that would likely
reduce some of the financial costs created by initiating the proposal

• A balanced argument for and against the proposal from the scientific perspective
of a geneticist

• A balanced argument for and against the proposal from the perspective of a policy
maker (e.g., a politician or a religious leader)

Continued

You have now completed the examination. If you have time ,
you may wish to check your answers.

BIOLOGY DATA

Symbol

Description

area

births during time interval

per capita births (

deaths during time interval

per capita deaths (^yy)

population density

carrying capacity

population size

change in population size

PG%

population growth (percent)

per capita population growth rate
(b-d)

volume

Equations

Subject

Equation

Hardy- Weinberg principle

p1 +2pq + qi =\

n N

Population density

Dp — or Dp —

Change in population size

AN = (factors that increase pop.) — (factors that decrease pop.)

AN x 100%

Population growth (%)

BIOLOGY DATA

Abbreviations for Some Hormones

Hormone

Abbreviation

Adrenocorticotropin hormone

ACTH

Antidiuretic hormone

ADH

Follicle stimulating hormone

FSH

Human chorionic gonadotropin

HCG

Luteinizing hormone

LH (formerly ICSH in males)

Parathyroid hormone

PTH

Prolactin

PRL

Somatotropin (human growth hormone or growth hormone)

STH (HGH or GH)

Thyroid stimulating hormone

TSH

Pedigree Symbols

□

O-n

o-n

■ OtO

■ [W

Male

Female

Mating

Mating between
close relatives

Offspring listed in
birth order. Roman
numerals symbolize
generations. Arabic
numbers symbolize
birth order within
generation.

Identical

twins

Non-identical

twins

Affected

individuals

Deceased

offspring

Offspring of
unknown sex

BIOLOGY DATA

Messenger RNA Codons and Their Corresponding Amino Acids

E C

N D

S E

uuu

Phe

ucu

Ser

UAU

Tyr

UGU

Cys

uuc

Phe

ucc

Ser

UAC

Tyr

UGC

Cys

UUA

Leu

UCA

Ser

UAA

STOP**

UGA

STOP**

UUG

Leu

UCG

Ser

UAG

STOP**

UGG

Trp

CUU

Leu

ecu

Pro

CAU

His

CGU

Arg

cue

Leu

ccc

Pro

CAC

His

CGC

Arg

CUA

Leu

CCA

Pro

CAA

Gin

CGA

Arg

CUG

Leu

CCG

Pro

CAG

Gin

CGG

Arg

AUU

lie

ACU

Thr

AAU

Asn

AGU

Ser

AUC

lie

ACC

Thr

AAC

Asn

AGC

Ser

AUA

lie

ACA

Thr

AAA

Lys

AGA

Arg

AUG

Met or START*

ACG

Thr

AAG

Lys

AGG

Arg

GUU

Val

GCU

Ala

GAU

Asp

GGU

Gly

GUC

Val

GCC

Ala

GAC

Asp

GGC

Gly

GUA

Val

GCA

Ala

GAA

Glu

GGA

Gly

GUG

Val

GCG

Ala

GAG

Glu

GGG

Gly

* Note: AUG is an initiator codon but also codes for the amino acid methionine.
** Note: UAA, UAG, and UGA are terminator codons.

Abbreviations for Amino Acids Information About Nitrogen Bases

Amino Acid

Abbreviation

Alanine

Ala

Arginine

Arg

Asparagine

Asn

Aspartate

Asp

Cysteine

Cys

Glutamate

Glu

Glutamine

Gin

Glycine

Gly

Histidine

His

Isoleucine

Leucine

Leu

Lysine

Lys

Methionine

Met

Phenylalanine

Phe

Proline

Pro

Serine

Ser

Threonine

Thr

Tryptophan

Trp

Tyrosine

Tyr

Valine

Val

Nitrogen Base

Classification

Abbreviation

Adenine

Purine

Guanine

Purine

Cytosine

Pyrimidine

Thymine

Pyrimidine

Uracil

Pyrimidine

No marks will be given for work done on this page.

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